It is regarded that a favorable condition for astronomical photographing is extremely dark surrounding environment. When the astronomical photographing is performed under such a favorable condition, it has been difficult to adjust the angle of view during photographing by an imaging apparatus in which a so-called live view image is displayed on an electronic view finder (EVF) or the like.
This is because immediate responsiveness is considered to be very important in original settings of the imaging apparatus that displays a live view image for adjusting the angle of view, and the exposure time is previously set so as not to exceed a certain period of time. Without an upper limit of the exposure time during photographing, a moving object may be blurred, for example, when the moving object is photographed.
Thus, the upper limit of the exposure time is usually determined, and if the surroundings are extremely dark and the minimum amount of light necessary to recognize the angle of view cannot be secured, the live view image becomes completely dark, such that a user cannot determine the angle of view. In particular, in cases where the amount of light is extremely small, a gain is forcedly increased, causing only red noise to stand out in the live view image.
As a result of this, a user has to repeat the steps of photographing a still image to check the photographed result and adjusting the angle of view to photograph the image again, when the user adjusts the angle of view in astronomical photographing, for example, so as to put mountains in the lower ⅓ area of the image with sky occupying the rest of the image. Astronomical photographing requires long exposure of 30 seconds to several minutes to photograph a still image. It has, therefore, been highly burdensome step for the user to repeatedly photograph images to adjust the angle of view.
An imaging apparatus including a button to interrupt exposure of a live view display during photographing in the dark place, to enable start of new exposure of a live view image at timing designated by a user is proposed (e.g., see Patent Document 1).
Further, an imaging apparatus capable of accepting changes in the updating cycle of an image, a gain value, or an aperture value during the display of the live view image is proposed (e.g., see Patent Document 2).